package com.wc.codeforces.总结题.Kevin_and_Geometry;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.util.Arrays;
import java.util.StringTokenizer;

/**
 * @Author congge
 * @Date 2025/5/5 10:03
 * @description
 * https://codeforces.com/contest/2061/problem/B
 */
public class Main {
    /**
     * 思路：
     * 找到两个相同的位置
     * 等腰梯形, 只需要考虑是否有两个相等的数即可
     * 不太对, 还得考虑 上下底边必须满足 abs(a - b) < 等腰的边 * 2
     * 如果 abs(a - b) >= 腰 * 2, 那么怎么都放不下腰
     */
    static FastReader sc = new FastReader();
    static PrintWriter out = new PrintWriter(System.out);
    static int N = 200010;
    static int[] a = new int[N];
    static int n;

    public static void main(String[] args) {
        int T = sc.nextInt();
        while (T-- > 0) {
            n = sc.nextInt();
            for (int i = 1; i <= n; i++) a[i] = sc.nextInt();
            Arrays.sort(a, 1, n + 1);
            int l = -1, r = -1, id = -1;
            for (int i = 1; i <= n; i++) {
                if (a[i] == a[i - 1]) {
                    if (l == -1) {
                        l = a[i];
                        id = i - 1;
                        i++;
                    } else {
                        r = a[i];
                        break;
                    }
                }
            }
            if (l != -1 && r != -1) out.printf("%d %d %d %d\n", l, l, r ,r);
            else if (l == -1) out.println(l);
            else {
                // 把这两个数删除了
                for (int i = id, j = id + 2; j <= n; i++, j++) a[i] = a[j];
                boolean success = false;
                for (int i = 2; i <= n - 2; i++) {
                    if (a[i] - a[i - 1] < l * 2) {
                        out.printf("%d %d %d %d\n", l, l, a[i], a[i - 1]);
                        success = true;
                        break;
                    }
                }
                if (!success) out.println(-1);
            }
        }
        out.flush();
    }
}

class FastReader {
    StringTokenizer st;
    BufferedReader br;

    FastReader() {
        br = new BufferedReader(new InputStreamReader(System.in));
    }

    String next() {
        while (st == null || !st.hasMoreElements()) {
            try {
                st = new StringTokenizer(br.readLine());
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        return st.nextToken();
    }

    int nextInt() {
        return Integer.parseInt(next());
    }

    String nextLine() {
        String s = "";
        try {
            s = br.readLine();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return s;
    }

    long nextLong() {
        return Long.parseLong(next());
    }

    double nextDouble() {
        return Double.parseDouble(next());
    }

    // 是否由下一个
    boolean hasNext() {
        while (st == null || !st.hasMoreTokens()) {
            try {
                String line = br.readLine();
                if (line == null)
                    return false;
                st = new StringTokenizer(line);
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        }
        return true;
    }
}

